This invention relates to a method for texturizing a mycelial fungal mass for use as a foodstuff.
Existing methods of working an amorphous mass of proteinaceous substance, for example, a mass derived from soya or from cereals or other vegetable sources, are well known and are employed in an attempt to provide a sufficient degree of random texturizing to make the substance readily acceptable as a foodstuff for humans.
U.S. Pat. No. 3,759,715, issued to Loepiktie et al on Sept. 18, 1973, discloses a method of producing an expanded protein food product having resiliency, chewiness and mouthfeel characteristics of real meat comprising the sequential steps of forming a dough of a secondary protein source material (vegetable protein) and an aqueous liquid; confining the dough so that a major portion of the surface of the dough is confined and a smaller portion of the surface of the dough is unconfined; exposing the partially confined dough to a heated atmosphere at a pressure between about 80 and 120 psi; and releasing the pressure to cause the partially confined dough to expand in the direction of the unconfined portion of the dough and form an expanded food product.
U.S. Pat. No. 3,814,823, issued to Yang et al on June 4, 1974, discloses a process for forming a meat-like, protein-containing product having unidirectional parallel fiber structure similar to that of natural meat fiber structure. The process comprises forming a protein mix containing from 30-100% by weight of a heat coagulable protein; adjusting the moisture content of the protein mix to form a wet mix having a moisture content within the range of from 20%-80% by weight of the wet mix; mixing the wet mix to provide a coherent workable protein dough; and thereafter subjecting the coherent workable protein dough to nonturbulent stretching and heat at a temperature above the heat-coagulation temperature of the heat-coagulable protein to provide a unidirectional, parallel, meat-like fiber structure. Vegetable or animal protein are disclosed as being useful as the heat-coagulable protein.
Mycelial fungi grown under controlled conditions in a fermenter are also a source of protein and it is to the texturizing of mycelial fungi with the particular aim of simulating meat that the present invention is concerned. A mycelial fungal mass is anisotropic in that manipulation of the mass will result in an irregular structure being imparted to the mass. A mycelial fungal mass is made up of groups of hyphae in random order and so as to make the mass acceptable as a foodstuff for humans the mass must be given a texture, preferably resembling the texture of a known foodstuff, for example, meat. In resembling meat the mass must have, inter alia, the layered and fibrous appearance of meat and also the chewiness of meat.
It is the main object of this invention to provide a method for texturizing a mycelial fungal mass so as to give to the mass a texture which is analogous to the texture of meat or fish.
U.S. Pat. No. 3,939,284, issued to Akin et al on Feb. 17, 1976, discloses a process for imparting meat-like texture to mixtures of single-cell protein material combined with plant protein materials and/or animal protein materials. The process comprises passing a mixture containing about 5 to about 50% of single-cell protein through a pre-conditioning zone wherein the moisture level is adjusted to about 20-45%; extruding the moisturized protein mixture at a temperature within the range of 210.degree.-385.degree. F. to provide a shaped extrudate; drying the extrudate at temperatures ranging from about 130.degree. to about 350.degree. F.; and cooling the dried extrudate. The patent further discloses that the shaped extrudate may be pulled immediately, exposed to a friction force by passing it through differential speed rollers, or cooled, rehydrated and exposed to a friction force by passing it through differential speed rollers, prior to drying the extrudate.
Prior art processes for texturizing a protein mass generally require high-temperature treatment, elevated pressure and/or relatively involved treatment. There exists a need for alternative and less complex texturizing processes.